Rated for temperature drops to 40°, the Boundary 40 Sleeping Bag from Slumberjack is designed to offer warmth and comfort during your outdoor trips. This mummy-style sleeping bag maintains warm all-body contact while allowing you enough room for comfortable movement. It proprietary Slumberloft synthetic insulation provides a thermal barrier against cold, and offset quilted construction further improves the ability to retain heat. A zipper draft tube with anti-snag design helps prevent heat leakage through the seams. Lockable zippers prevent accidental opening and exposure to the elements that may occur due to movement while sleeping. To keep your head and neck warm, the flip-over hood is fully insulated and can be turned inside out to expose its flat or contoured side. While the flat surface is more suitable for warmer nights, the contoured side will retain more heat and keep you warmer when outside temperatures drop. The hood also has a draft collar that creates a tight insulation barrier for your chest area from your neck down. To offer water-resistant protection, the sleeping bag fabric is treated with durable water repellent (DWR).